We investigate the possibility that Bose–Einstein condensates, loaded on a 2Doptical lattice, undergo—at finite temperature—a Berezinskii–Kosterlitz–Thouless transition. We show that—in an experimentally attainable range of parameters—a planar lattice of Bose–Einstein condensates is described by the XY model at finite temperature. We demonstrate that the interference pattern of the expanding condensates provides the experimental signature of the Berezinskii–Kosterlitz–Thouless transition by showing that, near the critical temperature, the k = 0 component of the momentum distribution and the central peak of the atomic density profile sharply decrease. The finite-temperature transition for a 3D optical lattice is also discussed in this paper, and analogies with superconducting Josephson junction networks are stressed throughout the text.
Observable Signature of the Berezinskii-Kosterlitz-Thouless Transition in a planar lattice of Bose Einstein Condensates
SODANO, Pasquale;
2005
Abstract
We investigate the possibility that Bose–Einstein condensates, loaded on a 2Doptical lattice, undergo—at finite temperature—a Berezinskii–Kosterlitz–Thouless transition. We show that—in an experimentally attainable range of parameters—a planar lattice of Bose–Einstein condensates is described by the XY model at finite temperature. We demonstrate that the interference pattern of the expanding condensates provides the experimental signature of the Berezinskii–Kosterlitz–Thouless transition by showing that, near the critical temperature, the k = 0 component of the momentum distribution and the central peak of the atomic density profile sharply decrease. The finite-temperature transition for a 3D optical lattice is also discussed in this paper, and analogies with superconducting Josephson junction networks are stressed throughout the text.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.